61. Investigators concluded that human failure was not responsible for the fatal airplane crash last August, and since that time new

 and more stringent rules for identifying and reporting mechanical problems have been in effect. That accounts for the fact that 

reports of airplane mechanical problems have increased in frequency by 50 percent since last August. 

 Which one of the following is an assumption underlying the argument in the passage? 

 A.        Airplane travel is still relatively safe, despite the increase in reported mechanical problems. 

B.        Mechanical problems in airplanes have increased dramatically since last August. 

C.        Mechanical problems in airplanes have not increased by 50 percent since last August. 

D.       Airlines are less reluctant to report mechanical problems than they previously were. 

E.        Mechanical problems in airplanes have become easier to detect since last August. 

    答案是c       我选的是E.事故不是因为人为的错误引起的，那应该是因为机械的问题吧,怎么c反而说机械问题没那么多呢?

                       新的制度生效了,问题应该更容易被发现才对吧???  哪位牛人赐教一下,谢啦.

reports of airplane mechanical problems have increased in frequency by 50 percent since last August.”不成立。呵呵，仅供参考哦

啊?我觉得是更严格的规则出台,就把那些机械问题给检查报告出来了,才导致报告数量上升的.

主要是第二和第三句的That accounts for引起本题的argument，对报告实施新规则限制是因为：笔者认为报告数量不同寻常的多了起来与实际情况不符，“实际情况”就是本argument 的假设，假设认为应该报告的实际情况确实没有现在已报告的这么多

假如实际上故障增加了100%而报告只增加了50%,说明报告不够严格.

正因为实际故障数量不变或者变化小于50%,才说明报告比过去严格了.